The objective of this research is to bring the withdrawal signs exhibited by narcotic dependent subjects under stimulus control. Various auditory, olfactory, visual, social and drug-induced stimuli are being investigated for this purpose. Stimulus control over physiological and neurochemical measures of withdrawal distress is being attempted. Laboratory rats are made dependent by oral, intraperitoneal, or intravenous administration of increasing doses of narcotic analgesics. These administrations are paired appropriately with the stimuli under investigation in order to develop a conditional association between the paired stimulus and the narcotic effects. Initial results show that the stimuli repeatedly paired with narcotic administration to develop conditional properties in that they reduce several withdrawal signs when presented to the conditioned subject during withdrawal. Bibliographic references: Roffman, M. and Lal, H.: Stimulus control of hexobarbital narcosis and metabolism in mice. J. Pharmacol. Expt. Therap. 191, 358-369 (1974); Roffman, M., Desjardins, P. and Lal, H.: Conditioned tolerance to hexobarbital. In: Drug Addiction, Vol. 3, Neurobiology and Influences on Behavior, Ed. Singh, J.M. and Lal, H., p. 251-258, Stratton Intercontinental Medical Book Corp., New York (1974).